Database Management System 2079

Section A
Long Answer Questions
Attempt any TWO questions. [2 × 10 = 20]

1. What is a transaction? Draw a transaction state diagram and discuss the typical states that a transaction goes through during execution. [2+8]

2. What is a functional dependency? What are the four informal measures of quality for relational schema design? Explain. [10]

3. Explain the various symbols used in the E-R Model. [10]

Section B
Short Answer Questions
Attempt any EIGHT questions. [8 × 5 = 40]

4. What is NoSQL? Explain the NoSQL characteristics related to data models and query languages. [1+4]

5. What is the system log used for? What are the typical kinds of entries in a system log? [2+3]

6. What is normalization? Explain 2NF with example. [1+4]

7. What is meant by the concurrent execution of database transactions in a multiuser system? Discuss why concurrency control is needed, and give informal examples. [5]

8. Retrieve the Employee Name, Department Number, and Department Name of 'John Smith' using Relational Algebra. The relations are given below.
EMPLOYEE (Ssn, Fname, Lname, Bdate, Address, Sex, Salary, SuperSSN, Dno)
PROJECT (Pnumber, Pname, Plocation, Dnum)
WORKS_ON (Essn, Pno, Hours)
DEPARTMENT (Dname, Dnumber, Mgr_ssn, Mgr_start_date) [5]

9. Discuss the different types of failures. What is meant by catastrophic failure? [5]

10. What is the Relational Data Model? How is a relation different from a flat file? [5]

11. What is a database? Explain the characteristics of the Database Approach. [5]

12. What are the three layers of the Three-Schema Architecture? Explain. [5]